Project Summary Borderline Personality Disorder (BPD) is a common psychiatric disorder found in approximately 2% to 6% of the population and 20% of hospitalized psychiatric patients. It is characterized by intense and rapid mood changes, self-destructive behavior, sucidality, and tumultuous relationships. It has proved very difficult to treat with either medications or psychotherapy. Suicide rates of approximately 10% have been reported. In additional to the emotional costs of the suffering experienced by borderline patients and their loved ones, BPD patients typically function at a level substantially below that of individuals with comparable intellect and they consume a disproportionate share of mental health resources. The difficulty controlling emotion, so central to the disorder, has proved a particularly difficult to treat. The present study utilizes the latest neuroimaging findings in BPD to generate new ideas for the psychotherapy of the disorder. This project builds upon our previous neuroimaging work, which has shown that when BPD patients try to control their emotions by employing a method that healthy people frequently use quite effectively -- taking an emotional distance from what is upsetting - BPD patients are not able to quiet down the part of their brain that sends out emotional alarm signals. The objective of the present study is to determine whether giving BPD patients special training in using this healthy distancing stragegy can help them to improve their ability to regulate their emotions and return their brain activity to a more normal pattern. We will do this by using fMRI to record brain activity as BPD subjects try to use distancing to reduce their emotional reactions to upsetting pictures before any training, then to have them receive specific training in the distancing strategy. After this training we will again obtain an fMRI scan to determine whether their pattern of brain activation has normalized and whether they have been able to better reduce their negative reactions to the pictures. If this is effective, it will show that such training may help BPD patients better regulate their emotions and would support a program to further develop and incorporate distancing training into the psychotherapy of BPD patients. A second objective of the present study is to determine whether the tendancy of BPD patients to become increasingly sensitized to negative situations when they are re-experienced (as shown by increased activity of the brain's emotional alarm system), will reduce with additional exposure, as it does in patients with phobias, or will continue to increase. Knowing this can help the therapist plan how to most therapeutically approach disturbing life experiences in the psychotherapy of BPD patients. This project represents an important step in brain imaging research since it applies information learned about brain activity patterns to develop new approaches to psychotherapy. It addresses a serious, prevalent and difficult to treat disorder.